Kochi University Repository

平成26年1月21日授与　高知大学乙総医博第27号　北添 紀子氏学位申請論文要約原文掲載は、Asia-Pacific Psychiatry　7(1), 1 March 2015, Pages 105-112.博士（医学）高知大

北添, 紀子

1 
 
The Autism-Spectrum Quotient in university students: Pattern of changes in its scores 
and associated factors 
 
Noriko Kitazoe 
 
Background 
It has been pointed out that an increasing number of students diagnosed as having 
Autism Spectrum Disorder (ASD) or ASD traits attend university, and that appropriate 
supports need to be provided to these students (Nevil and White, 2011). We think that it 
is important to contact students with ASD traits immediately after admission to check 
whether they are confused by the changes in the learning style, and if so, to provide 
support to them so as to assist them in resolving the difficulties in their lives. 
In Japan, at present, most students with ASD enter university prior to being 
diagnosed with ASD (Nishimura, 2006). To contact students before the occurrence of 
troubles, a screening test would be useful. Therefore, as part of student supports, 
students are evaluated by the Autism-Spectrum Quotient (AQ; Baron-Cohen et al., 
2001). The AQ is a self-administered questionnaire used to measure autism 
spectrum-related traits in young people and adults with normal intelligence 
(Baron-Cohen et al., 2001). It has a sensitivity and specificity of 79.3% and 97.7%, 
respectively (Baron-Cohen et al., 2001). On the other hand, there is also a report 
suggesting that the AQ-Japanese version’s (AQ-J) positive predictive value was low in a 
Japanese population (Kurita et al., 2005). It has been reported that the AQ identifies 
not only autistic traits but also mental health problems (Kurita and Koyama, 2006). 
Therefore, in this study, we investigated the AQ scores not only in a cross-sectional 
manner but also in a longitudinal manner, to examine the possibility of changes in AQ 
scores and associated factors. 
 
Methods 
1． Participants 
The first-year survey involved 3,932 students between fiscal years (FY) 2006 and 2009. 
The second-year survey involved 2,903 students who were registered as second-year 
students between FY 2007 and 2009. 
 
2． Measures 
The questionnaire consisted of the University Personality Inventory (UPI; Matsubara, 
1995), the AQ, and determination of whether or not the students desired mental health 
2 
 
consultation The UPI is a widely used tool in Japanese universities to screen students 
for neuroses, psychosomatic disorders, and other worries or anxieties (Kajita et al., 
2002). 
 
3． Procedures 
A paper describing the purpose, methods, and handling of the survey was distributed at 
the time of student orientation, and responses were obtained from students who agreed 
to cooperate with the health checkup. For second-year students, only the AQ was 
administered. 
 
Results 
1． Initial survey 
Valid responses were obtained from 3,427 (responses rate 87.2%). The number of 
students with AQ scores greater than or equal to 33 was 113 (3.3%). Of the total of 486 
students who were interviewed, ASD was diagnosed in 22. The sensitivity and 
specificity of the AQ for the diagnosis of ASD were 81.8% and 92.0%, respectively. The 
score on the AQ was significantly higher in the high-UPI group. The rate of desire to 
receive mental health consultation is significantly higher in group with ASD. Fifty five 
students with high-AQ were interviewed and divided into two groups according to 
whether they had ASD. No significant difference was observed in the total AQ score or 
UPI score between the two groups. However, a significant difference between the two 
groups was observed in one item of the AQ; unexpectedly significantly more subjects in 
the group without ASD disagreed with item 44 (I enjoy social occasions; disagreement 
was scored “1”). 
 
2． Comparison between the first and second-year survey results 
The number of students who responded to both the first and second-year surveys was 
319 (responses rate 11.0%). The high-AQ group in the first-year survey showed 
significantly decreased AQ scores in the survey conducted in the following year. 
Comparison of the scores between the first and second surveys showed significant 
differences in the scores for five items (3 of social skill, 1 of communication and 1 of 
attention to detail). 
 
Discussion 
1． Comparison with previous studies 
The findings of this study, differences in AQ scores between the sexes and among 
3 
 
departments, were consistent with the results previously reported (Baron-Cohen et al., 
2001; Wakabayashi et al., 2006). 
 
2． Counseling requests from students with ASD 
More students with ASD requested counseling than students without ASD did, 
suggesting that when students with ASD are asked “yes” or “no,” they choose a desire 
for consultation. In Japan, they are required to manage their lives on their own, and 
support is not often provided unless they request it. A somewhat standardized support 
system, such as classroom sessions or regular interviews with a personal tutor or 
healthcare worker, may be effective for these students. 
 
3． AQ and associated factors 
In this study, the AQ scores were more closely associated with the scores on the UPI 
(≥/< the cutoff point) than the sex or department of study. The group with AQ scores 
greater than or equal to the cutoff point in the first year showed significantly lower 
scores the following year. There are several possibilities explain the current result: 1) 
the associations between the AQ and UPI scores suggest that psychological symptoms 
are associated with the score on the AQ; 2) because the AQ is a self-administered 
questionnaire, even if the subjects’ traits themselves may not have changed, a change in 
their perceptions of themselves may affect the AQ scores; 3) the AQ score merely 
regressed to the mean.  
Among the AQ items, significant differences in the scores for social skills and 
communication-related items were observed between the first and second year surveys. 
Thus a student’s response to the AQ may vary for some items depending on their mental 
state. 
 
Acknowledgment 
This study was supported by a grant-in-aid for Scientific Research (C) (1853757) from 
Japan Society for the Promotion of Science. 
 
References 
Baron-Cohen S., Wheelwright S., Skinner R., Martin J., Clubley E. (2001) The  
Autism-Spectrum Quotient (AQ): evidence from Asperger syndrome/high functioning 
Autism, male and female, scientists and mathematics. J Autism Dev Disord. 31, 5–17. 
Kajita M., Takahashi T., Hayashi K., Fukuharu M., Sato J., Sato Y. (2002) Self-esteem  
and mental health characteristics especially among lean students surveyed by 
4 
 
University Personality Inventory. Psychiatry Clin Neurosci. 56, 123–129. 
Kurita H., Koyama T. (2006) Autism-Spectrum Quotient Japanese version measures  
mental health problems other than autistic trait. Psychiatry Clin Neurosci. 60, 373–
378. 
Kurita H., Koyama T., Osada H. (2005) Autism-Spectrum Quotient-Japanese version  
and its short form for screening normally intelligent persons with pervasive 
developmental disorders. Psychiatry Clin Neurosci. 59, 490–496. 
Matsubara T. (1995) University personality inventory. In: Mastubara T., ed.  
Shinritesutonyumon. Nihonbunkakagakusya, Tokyo, pp. 145–147 (in Japanese). 
Nevil R.E., White S.W. (2011) College students’ openness toward autism spectrum  
disorders: improving peer acceptance. J Autism Dev Disord. 41, 1619–1628. 
Nishimura Y. (2006) Support in the campus counseling room. Jpn J Learn Disabilit. 15,  
302–311 (in Japanese). 
Wakabayashi A., Baron-Cohen S., Wheelwright S., Tojo Y. (2006) The Autism-Spectrum  
Quotient (AQ) in Japan: a cross-cultural comparison. J Autism Dev Disord. 36, 263–
270. 
 


The Autism-Spectrum Quotient in university students: Pattern of changes in its scores and associated factors

永野マドセン, 泰子

岡本グフタフソン, 有花

清水, 由紀子

NAGANO-Madsen, Yasuko

OKAMOTO-Gustafsson, Yuka

SHIMIZU, Yukiko

Acquisition of L2 Japanese by Swedish learners
-The effect of a study stay in Japan on grammar and speech-

清家, 章

セイケ, アキラ

SEIKE, Akira

Regional Contribution and Research of Archaeological Sites

原崎, 道彦

HARASAKI, Michihiko

The Art of Relaxation

廣瀬, 淳一

大学における男女共同参画推進の教育的意義 ― 当事者意識の喚起による内発的学習―

小幡, 尚

松島, 朝秀

武藤, 整司

岡田, 健一郎

岩佐, 和幸

丸井, 一郎

原﨑, 道彦

講義「福島原発事故を考える （共通教育・2013年度）」の記録

Mohd Effendi Wasli

Hamsawi,  Sani

Ho Soo Ying

Mugunthan Perumal

Zatil, Aisyah Zainudin

Jonathan, Lat

Lee Pick Sean

Preliminary Assessment on the Growth Performance of Dryobalanops beccarii Dyer Planted under Enrichment Planting Technique at Gunung Apeng Forest Reserve, Sarawak, Malaysia

Ismail, Jusoh

Muhammad Anuar Aziz

63
Kuroshio Science 8-1, 63-67, 2014
Species composition and stand structure of an exploited  
mangrove forest
Ismail Jusoh1*, Muhammad Anuar Aziz1
1 Faculty of Resource Science and Technology, Universiti Malaysia Sarawak,
  94300 Kota Samarahan
Abstract
A study was conducted in a disturbed mangrove forest that had been gazetted as a national park in 
Sarawak, Malaysia. This study provides information regarding the status of disturbed mangroves and 
can be used as baseline data to support decision making in managing mangrove forests. The objec-
tives of this study were to determine the tree species composition and structure of an exploited man-
grove forest. This study was carried out in Kuching Wetland National Park (KWNP). Eight transects 
were established and in each transect sampling plots of 20 x 20m were established. All standing trees 
with a diameter at breast height (DBH) ≥ 5 cm within each plot were enumerated. Generally there 
are three major forest types in KNWP: mixed-mangrove forests, Sonneratia alba forest and heath or 
kerangas forest; a total of 98 species were recorded. Sonneratia alba forest dominates the sandy mud-
flats. However, their occurrence is not extensive, being confined to areas along the rivers, coastlines 
and estuaries of Batang Salak opposite Pulau Salak. The forest occurs on the seaward fringe as a 
narrow strip about 20 – 30 meters wide. The vast majority of the mangrove area can be classified as 
mixed-mangrove forest composed of Rhizophora apiculata and Rhizophora mucronta interspersed 
with Xylocarpus granatum, Avicennia alba and Nypa fructicans. More than 60% of the mangroves are 
pole size with a DBH between 5 and 10 cm. Avicennia alba recorded the highest basal area with 4.5 
m2/ha followed by Rhizophora apiculata (3.8 m2/ha) and Avicennia marina (1.3 m2/ha). Some areas 
in KNWP are made up of heath forests scattered throughout the interior of the park. The heath forest 
has a uniform single-layered canopy with trees reaching up to 22 m in height. There are no mangrove 
species in the heath forest and the common trees are Syzygium ochneocarpa, Whiteodendron moulto-
nianum and Casuarina sumatrana. In general, the species composition in KNWP is rich and the 
regeneration status is good.  
Key words: Mangroves, Kuching Wetland National Park, Stand structure, Species composition, Heath 
forest
*Corresponding author: e-mail jismail@frst.unimas.my
Introduction
The total area of mangrove forest in Sarawak is 
approximately 127,736 ha, which is about 1% of the 
total area of Sarawak (Abg Ahmad et al. 2008). The 
majority, about 80% of the state’s mangrove forest, is 
found in the Kuching and Mukah Divisions. Another 5% 
is found in the Limbang Division. The remaining 15% 
of forest areas are located in Sri Aman, Sibu and Miri. 
In Sarawak, the management of mangrove forest began 
in the 1920’s and the main objective was to sustain the 
production of mangrove-related products (Abg. Ahmad 
2008). 
The area now making up the current Kuching 
Wetland National Park was exploited by licensed con-
tractors prior to its incorporation as a national park. After 
the creation of KWNP in 2002 and the Ramsar site in 
2005, extraction for mangrove poles continued. However, 
after the establishment of KWNP, the license to extract 
mangroves was only given to locals living in the vicinity 
of the national park. For the area to continue providing 
ecological and commercial benefits mangrove forests 
must remain intact with minimal or no disturbance. The 
park provides protection of the coastline, various villages, 
farms and some areas of Kuching from erosion, salt 
intrusion, storm damage, flooding and siltation. Rapid 
development in the surrounding area will certainly have 
an impact on the park vegetation due to the increasing 
clearing of mangroves for agricultural activities, tourism, 
housing and urbanization. Nevertheless, information 
64
Species composition and stand structure of an exploited mangrove forest
regarding the park vegetation impacted by the continued 
mangrove extraction is scarce. Comprehensive species-
specific data is important for implementing conservation 
initiatives including regulation of resource extraction and 
clearing (Polidoro et al., 2010). The objectives of this 
study were to determine tree species composition and 
structure of an exploited mangrove forest. The data can 
serve as a baseline in managing the park.
Materials and Methods
Sampling
The study was carried out using eight transects. 
Along each transect, sampling plots of 20 x 20 m were 
established. Except for the heath forest, the survey area 
experiences daily tides and the soil is somewhat water-
logged. The area is relatively flat with occasional low 
and small mud mounds. In each plot, all standing trees 
with a diameter at breast height (dbh) ≥ 5 cm within each 
plot were enumerated. The tree diameter at breast height 
(i.e. 1.30 m above ground level) was measured over bark 
to the nearest cm. Enumerated trees were identified up to 
the species level. The identification was based on bark, 
slash and leaf characteristics. However, if the species of 
the tree could not be identified, it was sufficient to iden-
tify the plant up to genus level. Trees with a diameter 
of five cm and below were classed as saplings and were 
recorded. Tree diameters at breast height were measured 
over bark to the nearest cm using a diameter tape. Total 
tree heights were estimated using Suunto Clinometer. 
Results and Discussion
Forest Type
Generally there are three major forest types in 
KNWP: mixed-mangrove forests, Sonneratia alba 
(perepat) forest and heath or kerangas forest. Many 
of the forest subtypes classified by Chai (1975) were 
observed in KNWP, however, the distinctive features 
were not obvious due to the continuous extraction of 
mangroves. Sonneratia alba (Perepat) forest domi-
nated the sandy mudflats. However, their occurrence is 
not extensive, being confined to areas along the rivers, 
coastlines and estuaries of Batang Salak opposite Pulau 
Salak. The mangrove area occurs on the seaward fringe 
as a narrow strip about 20 – 30 meters wide. This spe-
cies colonizes newly formed silty mudflats and is seen 
as a pure stand. Sonneratia alba trees are the host trees 
of fireflies (Pteroptyx tener) and flashing is evident at 
dusk. The leaves of Sonneratia alba is the main source 
of food for the proboscis monkey (Nasalis larvatus) of 
Borneo (Salter et al. 1985). The presence of the pro-
boscis monkey is very noticeable with single monkeys 
or groups of three or four monkeys being present during 
daytime hours  and consuming Sonneratia alba leaves. 
Sonneratia leaves contain high levels of protein, phos-
phorus and potassium (Yeager et al., 1997).
The majority of the mangrove area is classified as 
being made up of mixed-mangrove species. This area is 
composed of Rhizophora apiculata (Bakau minyak) and 
Rhizophora mucronta (Bakau kurap) interspersed with 
Xylocarpus granatum, Avicennia alba and Nypa fructi-
cans. Young Rhizophora apiculata stands dominate the 
river, tributaries and channel banks. The ground, which 
is usually silty and composed of sandy-loam soil, is 
totally covered by dense, interlocking and tangled stilt 
roots. Bakau minyak regenerates very well (Chai 1982). 
Old Rhizophora apiculata trees are found on higher 
ground. The trees are straight and pole-like, and most 
of the pole-size (4 – 10 cm) trees in KNWP have been 
extracted for commercial use. Rhizophora mucronta is 
generally found to be less extensive than Rhizophora 
apiculata. In KNWP, Rhizophora apiculata is associated 
with Avicennia alba, Xylocarpus granatum, Nypa fruc-
ticans, Bruguiera sexangula, Bruguiera gymnorrhiza, 
Kandelia candel. The associated species vary according 
to soil type, estuarine upstream location, and tidal posi-
tion. In frontal stands, young Rhizophora apiculata man-
groves may be associated with Avicennia alba and Nypa 
fructicans. The occurrence of Xylocarpus granatum in 
drier ground is associated with Bruguiera spp. and older 
Rhizophora apiculata. On the landward sites where 
the ground is much drier, mixtures of Lumnitzera spp., 
Excoecaria agallocha, Kandelia candel and Xylocarpus 
granatum are common.
Some areas in KNWP are made up of heath forests 
scattered throughout the interior of the park (Fig. 2). The 
heath forest occurs on higher and drier ground of about 
5-6 m a.s.l. and receives no tidal inundation. These for-
ests are extremely different from the mangrove forest in 
structure and species composition and they have a uni-
form single-layered canopy with trees reaching up to 22 
m in height. 
Species composition
A total of 98 species were recorded in the KNWP 
(Table 1). Of that total, about 36% or 23 species were 
trees in the mangrove environment. According to 
Tomlinson’s (1986) definition, 14 species (six families) 
were major mangroves, four species (four families) were 
65
Ismail Jusoh, Muhammad Anuar Aziz
minor mangroves and five species (four families) were 
mangrove associates. Tomlinson’s (1986) classification 
of mangroves divided them according to their features 
and morphological adaptations: major mangroves are a 
group of plants that are adapted to a wet, saline habitat, 
are found exclusively in that mangrove habitat and can 
form a pure stand. Minor mangroves are groups of plants 
that do not occur in exclusively mangrove habitats, 
include inconspicuous vegetation, may occupy peripheral 
habitats and rarely form pure stands. Mangrove associ-
ates are plants present in mangrove habitats that do not 
show obvious morphological adaptations that can deal 
with the demanding mangrove habitat and may occur 
together with terrestrial vegetation. 
In the mixed-mangrove area, the three dominant 
species were Rhizophora apiculata, with an importance 
value (IV) of 29.4% followed by Avicennia alba (19.9%) 
and Ceriops tagal (10.6%). The top ten most dominant 
species as indicated by the IV is listed in Table 2. Of the 
14 major mangroves, four -- Avicennia alba, A. marina, 
Sonneratia alba and Lumnitzera littorea --  are listed as 
protected plants under the ‘Wildlife Protection Ordinance 
Sarawak 1998 (WPOS 1998). Avicennia alba and A. 
marina are probably abundant in the area as their timber 
has limited commercial value. Ecologically these two 
species are very important as they exhibit a wide physi-
ological tolerance and provide a conducive environment 
for other mangroves species to become established.
The protected species of special concern is 
Sonneratia alba, because the leaves are a food source for 
the endangered Proboscis monkey, Nasalis larvatus. The 
distribution of S. alba is not widespread, and is confined 
only to newly formed sandy mudflats in sheltered areas 
of the park. Lumnitzera littorea is a commercially impor-
tant species and it is threatened by the loss of habitat pri-
marily due to extraction. By protecting this species from 
continuous extraction it is hoped that this species will 
continue to flourish. However, it should be noted that 
none of the species recorded here are listed in the IUCN 
Red List of threatened species.
Some areas in KNWP are made up of heath forests 
scattered throughout the interior of the park. The heath 
forest occurs on higher and drier ground of about 5-6 
m a.s.l. and receives no tidal inundation. The heath for-
ests are generally species-rich (73 species) compared 
with the adjacent mangrove forests and are extremely 
different from the mangrove forest in structure and 
species composition. In the heath forest, the two domi-
nant species recorded were Syzygium ochneocarpa and 
Whiteodendron moultonianum dominant species with IV 
at 14% and 12%, respectively (Table 3). Species from 
the Dipterocarpaceae family such as Cotylobium spp., 
Table 2. Importance value indices for the ten most dominant mangrove species in KWNP.
Table 3. Importance value indices for the six most dominant non-mangrove species in KWNP.
No. Species Family IV%
1. Rhizophora apiculata Rhizophoraceae 29.4
2. Avicennia alba Acanthaceae 19.9
3. Ceriops tagal Rhizophoraceae 10.6
4. Avicennia marina Acanthaceae 8.2
5. Excoecaria agallocha Euphorbiaceae 5.9
6. Ceriops decandra Rhizophoraceae 5.3
7. Xylocarpus granatum Meliaceae 5.1
8. Rhizophora mucronata Rhizophoraceae 4.1
9. Bruguiera sexangula Rhizophoraceae 3.1
10. Bruguiera parviflora Rhizophoraceae 2.5
No. Species Family IV%
1. Syzygium ochneocarpa Myrtaceae 14
2. Whiteodendron moultonianum Myrtaceae 12
3. Diospyros siamang Ebenaceae 6.6
4. Calophyllum spp. Calophyllaceae 5.4
5. Knema sp. Myristicaceae 5.4
6. Cotylelobium spp. Dipterocarpaceae 5.3
Table 1. Species distribution of Kuching Wetland National 
Park.
Mangrove category No. of species
Major mangroves 14
Minor mangroves 6
Mangrove associate 5
Non mangrove (Terrestrial flora) 73
Total 98
66
Species composition and stand structure of an exploited mangrove forest
Dipterocarpus spp., Hopea spp., Shorea spp. and Vatica 
spp. were also recorded. Other common species include 
Dacrydium spp. and Garcinia bancana, Oncosperma 
tigillarium and Baccaurea spp.
In general, the species composition in KNWP is 
rich. The Indo-Malaysian region has 48 mangrove spe-
cies (Duke et al. 1998) and in Sarawak the total number 
of mangrove species recorded was 40 (Chai 1975). The 
14 major mangrove and six minor species recorded in 
this study can be considered as diverse. In fact, by taking 
into account the non-mangrove trees species found in the 
heath forest within the park, KNWP has a high biological 
diversity of plants. 
Stand structure of Kuching Wetland National 
Park
More than 60% of the mangroves were pole-size 
with DBH between 5 and 10 cm. None of the trees 
recorded had a diameter of 30 cm or above. In the 
mangrove area excluding the heath forest, Rhizophora 
apiculata was recorded at the highest frequency with 548 
tree/ha (42%) followed by Ceriops tagal at 150 trees/
ha (15%) and Avicennia alba at 168 (13%) (Table 4). 
In term of basal area, Avicennia alba was recorded as 
having the highest basal area with 4.5 m2/ha followed by 
Rhizophora apiculata (3.8 m2/ha) and Avicennia marina 
(1.3 m2/ha). 
The dominance of pole-size trees indicates that the 
mangroves are capable of reestablishing themselves by 
means of seed germinations following extraction. This 
means that selective extraction of individual mangrove 
has little impact in terms of regeneration.   However, the 
established mangrove community lacks regular zona-
tion perhaps due to the level of extraction. Moreover, 
the park consists of extensive interconnecting streams 
and tidal creeks that make zonation difficult to establish. 
Meandering streams and irregular canals yield a mosaic 
community in mangroves (Tomlison, 1994). A com-
parative study on disturbed and undisturbed mangroves 
ecosystems in Semporna Sabah showed that the mean 
DBH in disturbed ecosystems ranged from 10 to 20 cm 
while a larger DBH of 23 to 35 was common in undis-
turbed ecosystems (Wah et al.  2011). Observers noted 
that diameter distribution in undisturbed mangroves was 
symmetrically distributed and irregularly distributed in 
disturbed mangroves. 
Conclusion
Generally there are three forest types in KWNP: 
mixed-mangrove forests, Sonneratia alba (perepat) forest 
and heath or kerangas forest. Zonation of mangroves 
in the area is not distinct due to the numerous streams 
and canals as well as exploitation. More than 60% of 
the mangroves are pole-size with a DBH between 5 and 
10 cm indicating a healthy mangrove forest due to good 
regeneration of propagules. The species composition in 
KNWP is rich. Taking into account the non-mangrove 
tree species found in the heath forest within the park, the 
plant diversity in KNWP is high.
References
Abg Ahmad, A.M., Hamden, M. and Ali, Y. 2008. 
Pengurusan dan Pemuliharaan Hutan Bakau Di 
Sarawak. Seminar Pemuliharaan Hutan Pesisiran 
Pantai Negara 2008, Kuantan Pahang, 28 – 29 
Oktober 2008.
Chai, P. K. (1975). The mangrove trees and shrubs of 
Sarawak. Malaysian Forester, 38(3), 187-208.
Chai, P.P.K. 1982. Ecological studies of mangroves 
in Sarawak. Ph.D. Thesis. Universiti Malaya, 
Malaysia (Unpublished).
Duke, N.C. Ball, M.C. and Ellison, J.C. 1998. Factors 
influencing biodiversity and distributional 
gradients in mangroves. Global Ecology and 
Biogeography Letter 7, 27-47. 
Polidoro, B.A.,  Carpenter, K.E., Collins, L., Duke, N.C., 
Ellison, A.M., Ellison, J.C., Farnsworth, E.J. 
Fernando, E.S., Kathiresan, K., Koedam, N.E., 
Livingstone, S.R.,Miyagi, T., Moore, G.E., Nam, 
N.M., Ong, J.E.,Primavera, J.H.,Salmo, S.G., 
Sanciangco, J.C., Sukardjo, S.,Wang, Y. & Yong, 
J.W.H. (2010). The loss of species: mangrove 
extinction risk and geographic areas of global 
Table 4. Tree density and the basal area per ha of six common mangroves in KWNP.
No. Species Tree density (No./ha) Basal area (m2/ha)
1. Rhizophora apiculata 548 3.8
2. Ceriops tagal 198 0.7
3. Avicennia alba 168 4.5
4. Excoecaria agallocha 80 0.6
5. Ceriops decandra 75 0.09
6. Avicennia marina 65 1.3
67
Ismail Jusoh, Muhammad Anuar Aziz
concern. PLoS ONE, 5(4), 1-10.
Salter, R.E., MacKenzie, N.A., Nightingale, N., Aken, 
K.M., and Chai P.K., P. 1985. Habitat use, 
ranging behaviour, and food habits of the pro-
boscis monkey, Nasalis larvatus (van Wurmb), in 
Sarawak. Primates. Vol. 26(4), 436-451.
Tomlinson, P.B. 1986. The botany of mangroves. 
Cambridge UK: Cambridge University Press.
 Wah, L.M., Mojiol, A.R. & Saleh, E. (2011). Diversity 
of mangroves ecosystems in sempurna mangrove 
forest. Bioscience 28, 8-17.
WPOS (1998) – Laws of Sarawak. Chapter 26: Wild 
life Protection Ordinance Sarawak (1998). 
Government of Sarawak. Percetakan Nasional 
Malaysia Berhad, Kuching, Sarawak. 
Yeager, C.P., Silver, S.C., and Dierenfeld, E.S. 1997. 
Mineral and phytochemical influences on foliage 
selection by the proboscis monkey (Nasalis lar-
vatus). American Journal of Primatology 41, 117-
128.


Species composition and stand structure of an exploited mangrove forest

Fathul, Yusro

Yeni, Mariani

Farah, Diba

Kazuhiro, Ohtani

Inventory of Medicinal Plants for Fever Used by Four Dayak Sub Ethnic in West Kalimantan, Indonesia

岩崎, 保道

Yasumichi, Iwasaki

Regional Promotion Utilizing Manga—Discussion on Sustainable Town Development

Kōchi University

Not a member yet

The Autism-Spectrum Quotient in university students: Pattern of changes in its scores and associated factors

Acquisition of L2 Japanese by Swedish learners -The effect of a study stay in Japan on grammar and speech-